[XFRM] IPv6: Fix dst/routing check at transformation.

IPv6 specific thing is wrongly removed from transformation at net-2.6.25.
This patch recovers it with current design.

o Update "path" of xfrm_dst since IPv6 transformation should
  care about routing changes. It is required by MIPv6 and
  off-link destined IPsec.
o Rename nfheader_len which is for non-fragment transformation used by
  MIPv6 to rt6i_nfheader_len as IPv6 name space.

Signed-off-by: Masahide NAKAMURA <nakam@linux-ipv6.org>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 21 insertions, 0 deletions

diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index 8023a3c0dad5..521cb6e12561 100644
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -1266,6 +1266,23 @@ static inline struct xfrm_dst *xfrm_alloc_dst(int family)
         return xdst;
 }
 
+static inline int xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst,
+                                 int nfheader_len)
+{
+        struct xfrm_policy_afinfo *afinfo =
+                xfrm_policy_get_afinfo(dst->ops->family);
+        int err;
+
+        if (!afinfo)
+                return -EINVAL;
+
+        err = afinfo->init_path(path, dst, nfheader_len);
+
+        xfrm_policy_put_afinfo(afinfo);
+
+        return err;
+}
+
 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev)
 {
         struct xfrm_policy_afinfo *afinfo =
@@ -1298,6 +1315,7 @@ static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
         int i = 0;
         int err;
         int header_len = 0;
+        int nfheader_len = 0;
         int trailer_len = 0;
         int tos;
         int family = policy->selector.family;
@@ -1352,6 +1370,8 @@ static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
                 dst_prev = dst1;
 
                 header_len += xfrm[i]->props.header_len;
+                if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT)
+                        nfheader_len += xfrm[i]->props.header_len;
                 trailer_len += xfrm[i]->props.trailer_len;
         }
 
@@ -1366,6 +1386,7 @@ static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
         /* Copy neighbout for reachability confirmation */
         dst0->neighbour = neigh_clone(dst->neighbour);
 
+        xfrm_init_path((struct xfrm_dst *)dst0, dst, nfheader_len);
         xfrm_init_pmtu(dst_prev);
 
         for (dst_prev = dst0; dst_prev != dst; dst_prev = dst_prev->child) {